- Wide resection of small intestine or other disease limiting drug absorption (e.g., gastric dumping syndrome, features of rapid small bowel transit time, absorption disorder after intestine surgery) 16. Patients of childbearing potential who do not agree to use generally accepted effective method of birth control during the study treatment period and for at least 6 months after the end of study treatment 17. Pregnant women or breastfeeding women. Women of childbearing potential whose pregnancy test result is positive 18. Bone marrow and organ function inappropriate for administration of study drug: I. Absolute neutrophil count < 1.5 x 109/L II. Platelet < 100 x 109/L III. Hemoglobin ≤ 9 g/dL IV. AST> 2.5 x ULN, ALT> 2.5 x ULN V. ALP > 2.5 x ULN VI. Total bilirubin > 1.5 x ULN VII. Serum creatinine > 1.5 x ULN or creatinine clearance ≤ 50 mL/min Creatinine clearance will be calculated by Cockcroft-Gault formula or collection of 24-hour urine, and patients with creatinine clearance of ≤ 50 mL/min will be excluded.